Kaishi Satomi

Bronchioloalveolar carcinoma (lepidic growth) component is a more useful prognostic factor than lymph node metastasis.

Introduction: Although many factors predictive of patient survival have been reported for lung cancer, no comparative studies have attempted to determine those that are most significant for practical medicine. Methods: We conducted a retrospective review of 139 patients who underwent complete resection of adenocarcinomas less than 2 cm in diameter between 1993 and 2000 at the National Cancer Center Hospital (Tokyo, Japan). The MIB-1 labeling index (LI), immunohistochemical staining for carcinoembryonic antigen (CEA), p53, p27, epidermal growth factor receptor (EGFR), phosphorylated-EGFR (pEGFR), Cox-2, neuronatin, &ggr;H2AX, and thyroid transcription factor-1 (TTF-1), the prevalence of a micropapillary pattern, and the ratio of the bronchioloalveolar cell carcinoma (BAC) or lepidic growth (LG) component were determined, and their significance as prognostic factors for lung adenocarcinoma was compared. Results: Univariate analysis showed that lymph node metastasis (p-N status), BAC/LG component, vascular invasion (p-V status), MIB-1 LI, pEGFR, and CEA were prognostically significant (p-N status: p < 0.0001, BAC/LG: p = 0.0005, p-V status: 0.002, MIB-1 LI: p = 0.005, pEGFR: p = 0.024, and CEA: p = 0.049). Multivariate analysis showed that only p-N status (p = 0.013) was of prognostic significance. However, BAC/LG component (p = 0.051) was a more reliable prognostic factor than p-N status in mixed adenocarcinoma with a BAC/LG component. Conclusion: In comparison with other immunohistochemical and histopathologic factors, BAC/LG component is independently and reliably prognostic for small adenocarcinoma of the lung, and, in particular, for the major histologic subtype (adenocarcinoma mixed subtype with BAC/LG), BAC/LG component is more reliably prognostic than lymph node metastasis.

Nuclear Grading of Primary Pulmonary Adenocarcinomas: Correlation Between Nuclear Size and Prognosis

According to the World Health Organization Classification of Tumors, the prognostic value of morphometric cytologic atypia has not been assessed in pulmonary adenocarcinoma.

Generation of Induced Pluripotent Stem Cells from Human Nasal Epithelial Cells Using a Sendai Virus Vector

The generation of induced pluripotent stem cells (iPSCs) by introducing reprogramming factors into somatic cells is a promising method for stem cell therapy in regenerative medicine. Therefore, it is desirable to develop a minimally invasive simple method to create iPSCs. In this study, we generated human nasal epithelial cells (HNECs)-derived iPSCs by gene transduction with Sendai virus (SeV) vectors. HNECs can be obtained from subjects in a noninvasive manner, without anesthesia or biopsy. In addition, SeV carries no risk of altering the host genome, which provides an additional level of safety during generation of human iPSCs. The multiplicity of SeV infection ranged from 3 to 4, and the reprogramming efficiency of HNECs was 0.08–0.10%. iPSCs derived from HNECs had global gene expression profiles and epigenetic states consistent with those of human embryonic stem cells. The ease with which HNECs can be obtained, together with their robust reprogramming characteristics, will provide opportunities to investigate disease pathogenesis and molecular mechanisms in vitro, using cells with particular genotypes.

Differences in the prognostic implications of vascular invasion between lung adenocarcinoma and squamous cell carcinoma.

OBJECTIVES Vascular invasion (VI) has been accepted as a universally important prognostic factor for patients with lung carcinoma. However, the clinical significance of VI in each of the histological subtypes has been unclear. The aim of the present study was to investigate differences in the clinicopathological implications of VI between adenocarcinoma and squamous cell carcinoma. METHOD A total of 336 patients were evaluated, of whom 81 were diagnosed as having peripheral-type squamous cell carcinoma, and 255 as having adenocarcinoma. RESULT Among the 336 patients, the five-year survival rates for those who were VI-positive and VI-negative were 38.4% and 76.3%, respectively, the difference being significant (p<0.0001). Multivariate analysis identified VI as an independent prognostic factor (hazard ratio: 1.86). Although the difference in cancer-free survival between VI-positive and -negative patients was statistically significant for adenocarcinoma (p<0.0001), it was not significant for squamous cell carcinoma (p=0.086). For adenocarcinoma, the difference between the survival curves for VI-positive and -negative patients was significant for the subtypes with a predominant lepidic (p<0.0001), papillary (p=0.0026), and acinar (p=0.0060) component, whereas that for the predominantly solid subtype was not significant (p=0.58). Squamous cell carcinomas were then divided into two groups on the basis of the diameter of vessels that had been invaded by the cancer cells: large-vessel invasion (LVI; 1000 μm or more) and small-vessel invasion (SVI; less than 1000 μm). Although there was no difference in the survival curves between the LVI and SVI groups, the LVI group showed a significantly higher incidence of cavity formation and distant metastasis. CONCLUSION We conclude that VI is a useful prognostic indicator in lung carcinoma, although the clinical implications of VI differ between adenocarcinoma and squamous cell carcinoma.

Increased cytoplasmic S100A6 expression is associated with pulmonary adenocarcinoma progression

S100A6 is a calcium‐binding protein implicated in many cellular processes and frequently upregulated in cancer. Recently it was reported that S100A6 is one of the genes having higher expression in adenocarcinoma mixed subtype with a bronchioloalveolar carcinoma (BAC) component than in pure BAC. To clarify the association of S100A6 expression with stepwise progression of lung adenocarcinoma, S100A6 protein expression was examined on immunohistochemistry in 92 formalin‐fixed and paraffin‐embedded lung adenocarcinomas. Both the nucleus and cytoplasm of the tumor cells were stained, and the nuclear and cytoplasmic expression of S100A6 was assessed individually. In addition, six frozen surgical specimens were selected, and the expression of S100A6 was confirmed on western blotting. As a result, although it was not possible to detect any significant correlation between nuclear S100A6 immunoreactivity and tumor progression, advanced adenocarcinoma had significantly higher cytoplasmic S100A6 expression than non‐invasive lesions or normal lung tissue (P < 0.05). Moreover, the BAC component tended to have weaker staining than any of the other components. These findings indicate that S100A6 may be associated with the stepwise progression and/or invasion of lung adenocarcinoma, especially BAC‐type adenocarcinoma. The present results suggest the utility of S100A6 immunohistochemistry as a marker for estimation of malignancy in adenocarcinoma with a BAC component.

ECT2 amplification and overexpression as a new prognostic biomarker for early-stage lung adenocarcinoma.

Genetic abnormality in early‐stage lung adenocarcinoma was examined to search for new prognostic biomarkers. Six in situ lung adenocarcinomas and nine small but invasive adenocarcinomas were examined by array‐comparative genomic hybridization, and candidate genes of interest were screened. To examine gene abnormalities, 83 cases of various types of lung carcinoma were examined by quantitative real‐time genomic PCR and immunohistochemistry. The results were then verified using another set of early‐stage adenocarcinomas. Array‐comparative genomic hybridization indicated frequent amplification at chromosome 3q26. Of the seven genes located in this region, we focused on the epithelial cell transforming sequence 2 (ECT2) oncogene, as ECT2 amplification was detected only in invasive adenocarcinoma, and not in in situ carcinoma. Quantitative PCR and immunohistochemistry analyses also detected overexpression of ECT2 in invasive adenocarcinoma, and this was correlated with both the Ki‐67 labeling index and mitotic index. In addition, it was associated with disease‐free survival and overall survival of patients with lung adenocarcinoma. These results were verified using another set of early‐stage adenocarcinomas resected at another hospital. Abnormality of the ECT2 gene occurs at a relatively early stage of lung adenocarcinogenesis and would be applicable as a new biomarker for prognostication of patients with lung adenocarcinoma.

Stratifin accelerates progression of lung adenocarcinoma at an early stage

BackgroundsAdenocarcinoma in situ (AIS) of the lung has an extremely favorable prognosis. However, early but invasive adenocarcinoma (eIA) sometimes has a fatal outcome. We had previously compared the expression profiles of AIS with those of eIA showing lymph node metastasis or a fatal outcome, and found that stratifin (SFN, 14-3-3 sigma) was a differentially expressed gene related to cell proliferation. Here, we performed an in vivo study to clarify the role of SFN in initiation and progression of lung adenocarcinoma.FindingsSuppression of SFN expression in A549 (a human lung adenocarcinoma cell line) by siSFN significantly reduced cell proliferation activity and the S-phase subpopulation. In vivo, tumor development or metastasis to the lung was reduced in shSFN-transfected A549 cells. Moreover, we generated SFN-transgenic mice (Tg-SPC-SFN+/−) showing lung-specific expression of human SFN under the control of a tissue-specific enhancer, the SPC promoter. We found that Tg-SPC-SFN+/− mice developed lung tumors at a significantly higher rate than control mice after administration of chemical carcinogen, NNK. Interestingly, several Tg-SPC-SFN+/− mice developed tumors without NNK. These tumor cells showed high hSFN expression.ConclusionThese results suggest that SFN facilitates lung tumor development and progression. SFN appears to be a novel oncogene with potential as a therapeutic target.

Detection of the G17V RHOA mutation in angioimmunoblastic T-cell lymphoma and related lymphomas using quantitative allele-specific PCR.

Angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) are subtypes of T-cell lymphoma. Due to low tumor cell content and substantial reactive cell infiltration, these lymphomas are sometimes mistaken for other types of lymphomas or even non-neoplastic diseases. In addition, a significant proportion of PTCL-NOS cases reportedly exhibit features of AITL (AITL-like PTCL-NOS). Thus disagreement is common in distinguishing between AITL and PTCL-NOS. Using whole-exome and subsequent targeted sequencing, we recently identified G17V RHOA mutations in 60–70% of AITL and AITL-like PTCL-NOS cases but not in other hematologic cancers, including other T-cell malignancies. Here, we establish a sensitive detection method for the G17V RHOA mutation using a quantitative allele-specific polymerase chain reaction (qAS-PCR) assay. Mutated allele frequencies deduced from this approach were highly correlated with those determined by deep sequencing. This method could serve as a novel diagnostic tool for 60–70% of AITL and AITL-like PTCL-NOS.

Pancreatic neuroendocrine tumor and solid-pseudopapillary neoplasm: Key immunohistochemical profiles for differential diagnosis

AIM To reveal better diagnostic markers for differentiating neuroendocrine tumor (NET) from solid-pseudopapillary neoplasm (SPN), focusing primarily on immunohistochemical analysis. METHODS We reviewed 30 pancreatic surgical specimens of NET (24 cases) and SPN (6 cases). We carried out comprehensive immunohistochemical profiling using 9 markers: Synaptophysin, chromogranin A, pan-cytokeratin, E-cadherin, progesterone receptor, vimentin, α-1-antitrypsin, CD10, and β-catenin. RESULTS E-cadherin staining in NETs, and nuclear labeling of β-catenin in SPNs were the most sensitive and specific markers. Dot-like staining of chromogranin A might indicate the possibility of SPNs rather than NETs. The other six markers were not useful because their expression overlapped widely between NETs and SPNs. Moreover, two cases that had been initially diagnosed as NETs on the basis of their morphological features, demonstrated SPN-like immunohistochemical profiles. Careful diagnosis is crucial as we actually found two confusing cases showing disagreement between the tumor morphology and immunohistochemical profiles. CONCLUSION E-cadherin, chromogranin A, and β-catenin were the most useful markers which should be employed for differentiating between NET and SPN.

Development of the dorsal ramus of the spinal nerve in the chick embryo: a close relationship between development and expression of guidance cues.

The spinal nerve, which is composed of dorsal root ganglion (DRG) axons and spinal motor axons, divides into ventral and dorsal rami. Although the development of the ventral ramus has been examined in considerable detail, that of the dorsal ramus has not. Therefore, we first examined the spatial-temporal pattern of the dorsal ramus formation in the chick embryo, with special reference to the projection to the dermamyotome and its derivatives. Next, we focused on two guidance molecules, chick semaphorin 3A (SEMA3A) and fibroblast growth factor 8 (FGF8), because these are the best candidates as molecules for controlling the dorsal ramus formation. Using in situ hybridization and immunohistochemistry methods, we clearly showed a close relationship between the spatial-temporal expression of SEMA3A/FGF8 and the projection of dorsal ramus fibers to the dorsal muscles. We further examined the axonal response of motor and DRG neurons to SEMA3A and FGF8. We showed that motor axons responded to both SEMA3A-induced repulsion and FGF8-induced attraction. On the other hand, DRG axons responded to SEMA3A-induced repulsion but not to FGF8-induced attraction. These findings suggest that FGF8-induced attraction may guide early motor axons beneath the myotome and that SEMA3A-induced repulsion may prevent these early motor axons from entering the myotome. Our results also imply that the loss of SEMA3A expression in the dorsal muscles may lead to the gross projection of the dorsal ramus fibers into the dorsal muscles. Together, SEMA3A and FGF8 may contribute to the proper formation of the dorsal ramus.